TM 1-1520-238-10
Change 9
9-1
CHAPTER 9
EMERGENCY PROCEDURES
Section I.
AIRCRAFT SYSTEMS
9.1 AIRCRAFT SYSTEMS.
This section describes the aircraft system emergencies
that may reasonably be expected to occur and presents
the procedures to be followed. Table 9-1 shows the mes-
sages displayed on the MASTER CAUTION panels, the
caution/warning panels, and the corrective action re-
quired. Emergency procedures are given in checklist form
when applicable. A condensed version of these proce-
dures is contained in the condensed checklist,
TM 1-1520-238-CL.
NOTE
The urgency of certain emergencies re-
quires immediate and instinctive action
by the pilot. The most important single
consideration is helicopter control. All
procedures are subordinate to this re-
quirement.
When continued flight is in question, due
to a loss of rotor RPM or reduction of
available power (as a result of equipment
malfunctions or environmental condi-
tions), the immediate corrective action
should be to adjust collective to maintain
Nr within limits and jettisoning of the air-
craft wing stores. After stores jettison,
torque requirements will be reduced by
approximately 1% torque per 200 lbs. of
weight reduction. This reduction in gross
weight will reduce the minimum single–
engine airspeed values.
The MASTER CAUTION segment
should be reset after each malfunction to
allow systems to respond to possible
subsequent malfunctions. If time permits
during a critical emergency, transmit a
MAYDAY call.
9.2 DEFINITION OF EMERGENCY TERMS.
Those steps that must be performed immediately in an
emergency situation are underlined. These steps must be
performed without reference to the checklist. When the
situation permits, non-underlined steps will be accom-
plished with use of the checklist.
a. The term LAND WITHOUT DELAY is defined as a
landing in which the primary consideration is continued
control of the aircraft and survival of the occupants. It is
meant to be more urgent than Land As Soon As Possible.
The situation may not permit the aircrew to continue to
maneuver the aircraft to a suitable landing area (e.g.,
open field). If maneuvering to an open area is not practi-
cal, then the crew must make the decision to land in an
area that will have the least amount of negative impact on
crew survivability. (e.g., Over dense forest, select an area
with the smallest trees, in a mountainous area, choose an
area with the least amount of slope)
b. The term LAND AS SOON AS POSSIBLE is de-
fined as landing at the nearest suitable landing area (e.g.,
open field) without delay. (The primary consideration is to
ensure the survival of occupants.)
c. The term “LAND AS SOON AS PRACTICABLE” is
defined as landing at a suitable landing area. (The primary
consideration is the urgency of the emergency.)
d. The term AUTOROTATE is defined as adjusting
the flight controls as necessary to establish an autorota-
tional descent.
